The crystal structures of four di­meth­oxy­benzaldehyde isomers

The crystal structures of four di­meth­oxy­benzaldehyde (C₉H₁₀O₃) isomers are reported and compared to the previously reported crystal structures of 3,4-di­meth­oxy­benzaldehyde and 2,6-di­meth­oxy­benzaldehyde. All di­meth­oxy­benzaldehyde mol­ecules in the crystal structure are nearly planar.

Key indicators

Structure: 23DMBz

• Single-crystal X-ray study
• T = 150 K
• Mean [sigma](C-C) = 0.001 Å
• R factor = 0.043
• wR factor = 0.130
• Data-to-parameter ratio = 37.2

Structure: 24DMBz

• Single-crystal X-ray study
• T = 150 K
• Mean [sigma](C-C) = 0.001 Å
• R factor = 0.039
• wR factor = 0.117
• Data-to-parameter ratio = 22.2

Structure: 25DMBz

• Single-crystal X-ray study
• T = 150 K
• Mean [sigma](C-C) = 0.001 Å
• R factor = 0.039
• wR factor = 0.124
• Data-to-parameter ratio = 34.9

Structure: 35DMBz

• Single-crystal X-ray study
• T = 150 K
• Mean [sigma](C-C) = 0.001 Å
• R factor = 0.042
• wR factor = 0.126
• Data-to-parameter ratio = 35.9

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Datablock: 2,3DMBz



Alert level C
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Datablock: 2,4DMBz



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Datablock: 2,5DMBz



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Datablock: 3,5DMBz



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Computing details

For all structures, data collection: APEX3 (Bruker, 2012); cell refinement: PEAKREF (Schreurs, 2013); data reduction: SAINT (Bruker, 2012); program(s) used to solve structure: SHELXT2014/4 (Sheldrick, 2015a); program(s) used to refine structure: SHELXL2016/6 (Sheldrick, 2015b); molecular graphics: PLATON (Spek, 2009), ShelXLe (Hübschle et al., 2011).

2,3-Dimethoxybenzaldehyde (23DMBz)

Crystal data

C9H10O3	Dx = 1.365 Mg m^−3
Mr = 166.17	Melting point: 322 K
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
a = 7.6152 (3) Å	Cell parameters from 6893 reflections
b = 15.5513 (6) Å	θ = 2.6–36.9°
c = 7.5891 (3) Å	µ = 0.10 mm^−1
β = 115.8831 (18)°	T = 150 K
V = 808.59 (6) Å^3	Block, colourless
Z = 4	0.49 × 0.45 × 0.16 mm
F(000) = 352

Data collection

Bruker D8 Quest APEX3 diffractometer	4126 independent reflections
Radiation source: sealed tube	3160 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.032
Detector resolution: 10.4 pixels mm^-1	θmax = 37.1°, θmin = 2.6°
φ and ω scans	h = −12→12
Absorption correction: multi-scan (SADABS; Krause et al., 2015)	k = −26→26
Tmin = 0.672, Tmax = 0.747	l = −12→12
17821 measured reflections

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.043	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.130	H-atom parameters constrained
S = 1.02	w = 1/[σ^2(Fo^2) + (0.0743P)^2 + 0.0948P] where P = (Fo^2 + 2Fc^2)/3
4126 reflections	(Δ/σ)max = 0.001
111 parameters	Δρmax = 0.60 e Å^−3
0 restraints	Δρmin = −0.24 e Å^−3

Special details

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
O01	0.84423 (8)	0.67610 (3)	0.72112 (7)	0.01819 (11)
O02	0.93597 (9)	0.50880 (4)	0.76827 (8)	0.02194 (12)
O03	0.42554 (9)	0.77393 (5)	0.22027 (10)	0.03084 (15)
C04	0.60779 (10)	0.65162 (5)	0.38944 (10)	0.01633 (12)
C05	0.79724 (10)	0.53265 (4)	0.58899 (9)	0.01586 (12)
C06	0.50903 (11)	0.59449 (5)	0.23432 (10)	0.02083 (14)
H06	0.410967	0.615175	0.113675	0.025*
C07	0.75191 (9)	0.62098 (4)	0.56613 (9)	0.01466 (12)
C08	0.55760 (11)	0.74397 (5)	0.36618 (11)	0.02121 (14)
H08	0.632072	0.781899	0.470279	0.025*
C09	0.69865 (11)	0.47667 (5)	0.43414 (11)	0.01968 (13)
H09	0.729027	0.417067	0.448365	0.024*
C10	0.55498 (11)	0.50806 (5)	0.25774 (11)	0.02239 (15)
H10	0.487993	0.469473	0.152498	0.027*
C11	1.04331 (11)	0.69266 (5)	0.75867 (12)	0.02355 (15)
H11A	1.113534	0.638043	0.778082	0.035*
H11B	1.106109	0.728092	0.876679	0.035*
H11C	1.045946	0.723144	0.646820	0.035*
C12	0.98881 (13)	0.41998 (5)	0.79585 (12)	0.02495 (16)
H12A	0.872738	0.385147	0.769517	0.037*
H12B	1.086092	0.410593	0.931161	0.037*
H12C	1.043851	0.403253	0.705808	0.037*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O01	0.0179 (2)	0.0172 (2)	0.0179 (2)	−0.00017 (17)	0.00634 (17)	−0.00429 (17)
O02	0.0282 (3)	0.0151 (2)	0.0174 (2)	0.00471 (19)	0.0052 (2)	0.00247 (17)
O03	0.0228 (3)	0.0306 (3)	0.0343 (3)	0.0108 (2)	0.0081 (2)	0.0124 (3)
C04	0.0142 (3)	0.0176 (3)	0.0168 (3)	0.0012 (2)	0.0064 (2)	0.0019 (2)
C05	0.0180 (3)	0.0140 (3)	0.0157 (2)	0.0007 (2)	0.0075 (2)	0.0007 (2)
C06	0.0171 (3)	0.0265 (4)	0.0164 (3)	−0.0016 (2)	0.0049 (2)	−0.0001 (2)
C07	0.0147 (3)	0.0138 (3)	0.0153 (2)	0.0003 (2)	0.0064 (2)	−0.00084 (19)
C08	0.0185 (3)	0.0207 (3)	0.0250 (3)	0.0049 (2)	0.0100 (3)	0.0050 (3)
C09	0.0240 (3)	0.0156 (3)	0.0207 (3)	−0.0029 (2)	0.0110 (3)	−0.0034 (2)
C10	0.0229 (3)	0.0240 (3)	0.0189 (3)	−0.0061 (3)	0.0078 (3)	−0.0057 (2)
C11	0.0193 (3)	0.0225 (3)	0.0254 (3)	−0.0045 (3)	0.0067 (3)	−0.0055 (3)
C12	0.0324 (4)	0.0170 (3)	0.0272 (3)	0.0085 (3)	0.0147 (3)	0.0064 (3)

Geometric parameters (Å, º)

O01—C07	1.3750 (8)	C06—H06	0.9500
O01—C11	1.4383 (10)	C08—H08	0.9500
O02—C05	1.3601 (8)	C09—C10	1.3960 (11)
O02—C12	1.4284 (9)	C09—H09	0.9500
O03—C08	1.2175 (9)	C10—H10	0.9500
C04—C07	1.3945 (9)	C11—H11A	0.9800
C04—C06	1.4029 (10)	C11—H11B	0.9800
C04—C08	1.4767 (10)	C11—H11C	0.9800
C05—C09	1.3901 (10)	C12—H12A	0.9800
C05—C07	1.4085 (9)	C12—H12B	0.9800
C06—C10	1.3807 (12)	C12—H12C	0.9800
C07—O01—C11	112.47 (6)	C05—C09—H09	120.0
C05—O02—C12	117.16 (6)	C10—C09—H09	120.0
C07—C04—C06	119.94 (7)	C06—C10—C09	120.82 (7)
C07—C04—C08	120.08 (6)	C06—C10—H10	119.6
C06—C04—C08	119.98 (6)	C09—C10—H10	119.6
O02—C05—C09	124.88 (6)	O01—C11—H11A	109.5
O02—C05—C07	115.51 (6)	O01—C11—H11B	109.5
C09—C05—C07	119.59 (6)	H11A—C11—H11B	109.5
C10—C06—C04	119.71 (7)	O01—C11—H11C	109.5
C10—C06—H06	120.1	H11A—C11—H11C	109.5
C04—C06—H06	120.1	H11B—C11—H11C	109.5
O01—C07—C04	120.23 (6)	O02—C12—H12A	109.5
O01—C07—C05	119.76 (6)	O02—C12—H12B	109.5
C04—C07—C05	119.96 (6)	H12A—C12—H12B	109.5
O03—C08—C04	123.28 (8)	O02—C12—H12C	109.5
O03—C08—H08	118.4	H12A—C12—H12C	109.5
C04—C08—H08	118.4	H12B—C12—H12C	109.5
C05—C09—C10	119.98 (7)
C12—O02—C05—C09	2.55 (11)	O02—C05—C07—O01	−1.05 (9)
C12—O02—C05—C07	−178.75 (6)	C09—C05—C07—O01	177.73 (6)
C07—C04—C06—C10	0.13 (11)	O02—C05—C07—C04	−178.28 (6)
C08—C04—C06—C10	−179.23 (7)	C09—C05—C07—C04	0.51 (10)
C11—O01—C07—C04	−108.70 (7)	C07—C04—C08—O03	−175.45 (7)
C11—O01—C07—C05	74.09 (8)	C06—C04—C08—O03	3.90 (11)
C06—C04—C07—O01	−177.61 (6)	O02—C05—C09—C10	178.31 (7)
C08—C04—C07—O01	1.75 (10)	C07—C05—C09—C10	−0.34 (11)
C06—C04—C07—C05	−0.40 (10)	C04—C06—C10—C09	0.03 (11)
C08—C04—C07—C05	178.96 (6)	C05—C09—C10—C06	0.08 (11)

2,4-Dimethoxybenzaldehyde (24DMBz)

Crystal data

C9H10O3	Dx = 1.374 Mg m^−3
Mr = 166.17	Melting point: 341 K
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
a = 15.1575 (8) Å	Cell parameters from 9286 reflections
b = 3.9638 (2) Å	θ = 2.8–30.5°
c = 14.6181 (8) Å	µ = 0.10 mm^−1
β = 113.8388 (19)°	T = 150 K
V = 803.35 (7) Å^3	Block, colourless
Z = 4	0.50 × 0.43 × 0.40 mm
F(000) = 352

Data collection

Bruker D8 Quest APEX3 diffractometer	2461 independent reflections
Radiation source: sealed tube	2171 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.020
Detector resolution: 10.4 pixels mm^-1	θmax = 30.5°, θmin = 2.8°
φ and ω scans	h = −21→21
Absorption correction: multi-scan (SADABS; Krause et al., 2015)	k = −5→5
Tmin = 0.685, Tmax = 0.746	l = −20→19
15236 measured reflections

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.039	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.117	H-atom parameters constrained
S = 1.03	w = 1/[σ^2(Fo^2) + (0.0714P)^2 + 0.196P] where P = (Fo^2 + 2Fc^2)/3
2461 reflections	(Δ/σ)max < 0.001
111 parameters	Δρmax = 0.40 e Å^−3
0 restraints	Δρmin = −0.24 e Å^−3

Special details

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
O01	0.08102 (5)	0.65429 (18)	0.10801 (5)	0.02325 (16)
O02	0.39771 (5)	0.76391 (19)	0.37610 (5)	0.02571 (17)
O03	0.31680 (6)	0.2357 (2)	0.56154 (5)	0.0358 (2)
C04	0.30419 (6)	0.6579 (2)	0.33618 (6)	0.01822 (17)
C05	0.27290 (6)	0.4771 (2)	0.40045 (6)	0.01952 (18)
C06	0.14709 (6)	0.6063 (2)	0.20292 (6)	0.01766 (17)
C07	0.24207 (6)	0.7210 (2)	0.23720 (6)	0.01809 (17)
H07	0.263957	0.839754	0.193881	0.022*
C08	0.11380 (6)	0.4292 (2)	0.26563 (6)	0.01980 (18)
H08	0.048785	0.354354	0.241536	0.024*
C09	0.17672 (6)	0.3653 (2)	0.36266 (6)	0.02020 (18)
H09	0.154643	0.242605	0.405167	0.024*
C10	0.11345 (7)	0.8119 (2)	0.03878 (7)	0.02355 (19)
H10A	0.133339	1.044263	0.060154	0.035*
H10B	0.060848	0.813520	−0.028047	0.035*
H10C	0.168300	0.685728	0.036939	0.035*
C11	0.33908 (7)	0.3954 (3)	0.50273 (7)	0.0272 (2)
H11	0.403821	0.471787	0.524941	0.033*
C12	0.43374 (7)	0.9262 (3)	0.31058 (8)	0.0276 (2)
H12A	0.425511	0.776125	0.254432	0.041*
H12B	0.502361	0.977611	0.347363	0.041*
H12C	0.397996	1.135995	0.285113	0.041*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O01	0.0204 (3)	0.0285 (3)	0.0187 (3)	−0.0020 (2)	0.0057 (2)	0.0016 (2)
O02	0.0180 (3)	0.0327 (4)	0.0249 (3)	−0.0049 (3)	0.0071 (2)	0.0042 (3)
O03	0.0340 (4)	0.0489 (5)	0.0239 (3)	−0.0020 (3)	0.0111 (3)	0.0108 (3)
C04	0.0169 (3)	0.0182 (4)	0.0204 (4)	0.0001 (3)	0.0084 (3)	−0.0010 (3)
C05	0.0211 (4)	0.0201 (4)	0.0186 (4)	0.0008 (3)	0.0093 (3)	0.0001 (3)
C06	0.0189 (4)	0.0163 (3)	0.0181 (3)	0.0013 (3)	0.0077 (3)	−0.0022 (3)
C07	0.0194 (4)	0.0176 (3)	0.0194 (4)	0.0003 (3)	0.0100 (3)	−0.0001 (3)
C08	0.0191 (4)	0.0194 (4)	0.0229 (4)	−0.0016 (3)	0.0106 (3)	−0.0018 (3)
C09	0.0229 (4)	0.0198 (4)	0.0218 (4)	−0.0003 (3)	0.0131 (3)	0.0000 (3)
C10	0.0269 (4)	0.0249 (4)	0.0188 (4)	−0.0002 (3)	0.0092 (3)	0.0011 (3)
C11	0.0251 (4)	0.0335 (5)	0.0215 (4)	−0.0011 (4)	0.0078 (3)	0.0034 (3)
C12	0.0215 (4)	0.0296 (5)	0.0337 (5)	−0.0017 (3)	0.0134 (4)	0.0068 (4)

Geometric parameters (Å, º)

O01—C06	1.3567 (10)	C07—H07	0.9500
O01—C10	1.4347 (11)	C08—C09	1.3756 (12)
O02—C04	1.3629 (10)	C08—H08	0.9500
O02—C12	1.4326 (11)	C09—H09	0.9500
O03—C11	1.2201 (12)	C10—H10A	0.9800
C04—C07	1.3934 (11)	C10—H10B	0.9800
C04—C05	1.4077 (11)	C10—H10C	0.9800
C05—C09	1.4057 (12)	C11—H11	0.9500
C05—C11	1.4608 (12)	C12—H12A	0.9800
C06—C07	1.3954 (11)	C12—H12B	0.9800
C06—C08	1.4007 (11)	C12—H12C	0.9800
C06—O01—C10	117.43 (7)	C08—C09—H09	119.2
C04—O02—C12	117.63 (7)	C05—C09—H09	119.2
O02—C04—C07	122.59 (7)	O01—C10—H10A	109.5
O02—C04—C05	116.35 (7)	O01—C10—H10B	109.5
C07—C04—C05	121.05 (7)	H10A—C10—H10B	109.5
C09—C05—C04	118.29 (7)	O01—C10—H10C	109.5
C09—C05—C11	120.43 (8)	H10A—C10—H10C	109.5
C04—C05—C11	121.24 (8)	H10B—C10—H10C	109.5
O01—C06—C07	123.34 (8)	O03—C11—C05	124.40 (9)
O01—C06—C08	115.29 (7)	O03—C11—H11	117.8
C07—C06—C08	121.37 (8)	C05—C11—H11	117.8
C04—C07—C06	118.72 (8)	O02—C12—H12A	109.5
C04—C07—H07	120.6	O02—C12—H12B	109.5
C06—C07—H07	120.6	H12A—C12—H12B	109.5
C09—C08—C06	118.95 (8)	O02—C12—H12C	109.5
C09—C08—H08	120.5	H12A—C12—H12C	109.5
C06—C08—H08	120.5	H12B—C12—H12C	109.5
C08—C09—C05	121.60 (8)
C12—O02—C04—C07	−4.23 (12)	O01—C06—C07—C04	−179.94 (7)
C12—O02—C04—C05	175.40 (8)	C08—C06—C07—C04	−0.36 (12)
O02—C04—C05—C09	179.48 (8)	O01—C06—C08—C09	179.01 (7)
C07—C04—C05—C09	−0.88 (13)	C07—C06—C08—C09	−0.60 (12)
O02—C04—C05—C11	−2.82 (13)	C06—C08—C09—C05	0.83 (13)
C07—C04—C05—C11	176.82 (8)	C04—C05—C09—C08	−0.11 (13)
C10—O01—C06—C07	4.17 (12)	C11—C05—C09—C08	−177.83 (8)
C10—O01—C06—C08	−175.43 (7)	C09—C05—C11—O03	−1.27 (16)
O02—C04—C07—C06	−179.28 (8)	C04—C05—C11—O03	−178.93 (10)
C05—C04—C07—C06	1.10 (12)

2,5-Dimethoxybenzaldehyde (25DMBz)

Crystal data

C9H10O3	Dx = 1.384 Mg m^−3
Mr = 166.17	Melting point: 321 K
Monoclinic, P21/n	Mo Kα radiation, λ = 0.71073 Å
a = 3.8780 (3) Å	Cell parameters from 9955 reflections
b = 11.5513 (7) Å	θ = 2.3–36.2°
c = 17.8153 (12) Å	µ = 0.10 mm^−1
β = 91.808 (2)°	T = 150 K
V = 797.66 (10) Å^3	Needle, colourless
Z = 4	0.74 × 0.38 × 0.13 mm
F(000) = 352

Data collection

Bruker D8 Quest APEX3 diffractometer	3873 independent reflections
Radiation source: sealed tube	3276 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.024
Detector resolution: 10.4 pixels mm^-1	θmax = 36.4°, θmin = 2.1°
φ and ω scans	h = −6→6
Absorption correction: multi-scan (SADABS; Krause et al., 2015)	k = −14→19
Tmin = 0.705, Tmax = 0.747	l = −29→29
30235 measured reflections

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.039	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.124	H-atom parameters constrained
S = 1.02	w = 1/[σ^2(Fo^2) + (0.0691P)^2 + 0.1755P] where P = (Fo^2 + 2Fc^2)/3
3873 reflections	(Δ/σ)max = 0.001
111 parameters	Δρmax = 0.54 e Å^−3
0 restraints	Δρmin = −0.22 e Å^−3

Special details

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
O01	0.70027 (15)	0.37815 (5)	0.56706 (3)	0.02308 (11)
O02	0.32551 (16)	0.55079 (5)	0.84287 (3)	0.02348 (12)
O03	0.81653 (19)	0.71583 (5)	0.60790 (3)	0.02970 (14)
C04	0.64196 (16)	0.53211 (5)	0.65291 (3)	0.01623 (11)
C05	0.54777 (16)	0.57451 (5)	0.72267 (3)	0.01719 (11)
H05	0.580616	0.654118	0.734217	0.021*
C06	0.44894 (18)	0.34122 (6)	0.68849 (4)	0.01849 (12)
H06	0.413247	0.261704	0.677056	0.022*
C07	0.40630 (16)	0.50128 (5)	0.77542 (3)	0.01656 (11)
C08	0.35490 (17)	0.38467 (6)	0.75789 (4)	0.01814 (12)
H08	0.255150	0.334576	0.793501	0.022*
C09	0.59531 (16)	0.41403 (5)	0.63571 (3)	0.01655 (11)
C10	0.79366 (19)	0.61160 (6)	0.59830 (4)	0.02189 (13)
H10	0.878085	0.579933	0.553220	0.026*
C11	0.6662 (2)	0.25766 (6)	0.55053 (4)	0.02393 (14)
H11A	0.787349	0.212440	0.589721	0.036*
H11B	0.766517	0.241337	0.501841	0.036*
H11C	0.421362	0.236493	0.548665	0.036*
C12	0.1987 (2)	0.47519 (7)	0.89872 (4)	0.02583 (15)
H12A	−0.020111	0.441090	0.880789	0.039*
H12B	0.161901	0.518945	0.944911	0.039*
H12C	0.367146	0.413466	0.908934	0.039*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O01	0.0330 (3)	0.0181 (2)	0.0185 (2)	−0.00401 (19)	0.00611 (18)	−0.00154 (16)
O02	0.0348 (3)	0.0174 (2)	0.0187 (2)	0.00073 (19)	0.00818 (19)	0.00082 (16)
O03	0.0450 (3)	0.0186 (2)	0.0256 (3)	−0.0097 (2)	0.0032 (2)	0.00350 (18)
C04	0.0178 (2)	0.0145 (2)	0.0164 (2)	−0.00141 (18)	0.00017 (18)	0.00262 (18)
C05	0.0197 (2)	0.0141 (2)	0.0178 (2)	−0.00057 (19)	0.00054 (19)	0.00188 (18)
C06	0.0222 (3)	0.0146 (2)	0.0186 (2)	−0.00275 (19)	0.0011 (2)	0.00149 (18)
C07	0.0179 (2)	0.0156 (2)	0.0163 (2)	0.00086 (19)	0.00157 (18)	0.00161 (18)
C08	0.0205 (3)	0.0158 (2)	0.0183 (2)	−0.00184 (19)	0.00202 (19)	0.00261 (18)
C09	0.0182 (2)	0.0155 (2)	0.0160 (2)	−0.00112 (19)	0.00031 (18)	0.00083 (18)
C10	0.0277 (3)	0.0191 (3)	0.0189 (3)	−0.0051 (2)	0.0018 (2)	0.0032 (2)
C11	0.0306 (3)	0.0194 (3)	0.0219 (3)	−0.0011 (2)	0.0020 (2)	−0.0034 (2)
C12	0.0322 (4)	0.0232 (3)	0.0227 (3)	0.0033 (3)	0.0109 (3)	0.0042 (2)

Geometric parameters (Å, º)

O01—C09	1.3655 (8)	C06—C09	1.3954 (9)
O01—C11	1.4280 (9)	C06—H06	0.9500
O02—C07	1.3757 (8)	C07—C08	1.3957 (9)
O02—C12	1.4232 (9)	C08—H08	0.9500
O03—C10	1.2189 (9)	C10—H10	0.9500
C04—C05	1.3952 (9)	C11—H11A	0.9800
C04—C09	1.4083 (9)	C11—H11B	0.9800
C04—C10	1.4738 (9)	C11—H11C	0.9800
C05—C07	1.3901 (9)	C12—H12A	0.9800
C05—H05	0.9500	C12—H12B	0.9800
C06—C08	1.3936 (9)	C12—H12C	0.9800
C09—O01—C11	116.90 (5)	O01—C09—C04	116.67 (5)
C07—O02—C12	116.67 (6)	C06—C09—C04	119.30 (6)
C05—C04—C09	119.89 (6)	O03—C10—C04	123.47 (7)
C05—C04—C10	119.37 (6)	O03—C10—H10	118.3
C09—C04—C10	120.73 (6)	C04—C10—H10	118.3
C07—C05—C04	120.57 (6)	O01—C11—H11A	109.5
C07—C05—H05	119.7	O01—C11—H11B	109.5
C04—C05—H05	119.7	H11A—C11—H11B	109.5
C08—C06—C09	120.27 (6)	O01—C11—H11C	109.5
C08—C06—H06	119.9	H11A—C11—H11C	109.5
C09—C06—H06	119.9	H11B—C11—H11C	109.5
O02—C07—C05	116.31 (6)	O02—C12—H12A	109.5
O02—C07—C08	124.18 (6)	O02—C12—H12B	109.5
C05—C07—C08	119.51 (6)	H12A—C12—H12B	109.5
C06—C08—C07	120.44 (6)	O02—C12—H12C	109.5
C06—C08—H08	119.8	H12A—C12—H12C	109.5
C07—C08—H08	119.8	H12B—C12—H12C	109.5
O01—C09—C06	124.03 (6)
C09—C04—C05—C07	−0.32 (9)	C11—O01—C09—C04	177.58 (6)
C10—C04—C05—C07	−179.56 (6)	C08—C06—C09—O01	178.78 (6)
C12—O02—C07—C05	−176.57 (6)	C08—C06—C09—C04	−0.97 (10)
C12—O02—C07—C08	3.41 (10)	C05—C04—C09—O01	−178.60 (6)
C04—C05—C07—O02	179.25 (6)	C10—C04—C09—O01	0.63 (9)
C04—C05—C07—C08	−0.72 (10)	C05—C04—C09—C06	1.16 (9)
C09—C06—C08—C07	−0.07 (10)	C10—C04—C09—C06	−179.60 (6)
O02—C07—C08—C06	−179.05 (6)	C05—C04—C10—O03	−6.37 (11)
C05—C07—C08—C06	0.92 (10)	C09—C04—C10—O03	174.39 (7)
C11—O01—C09—C06	−2.17 (10)

3,5-Dimethoxybenzaldehyde (35DMBz)

Crystal data

C9H10O3	Dx = 1.346 Mg m^−3
Mr = 166.17	Melting point: 319 K
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
a = 11.7602 (5) Å	Cell parameters from 9794 reflections
b = 13.8957 (6) Å	θ = 2.5–36.4°
c = 11.4352 (5) Å	µ = 0.10 mm^−1
β = 118.642 (2)°	T = 150 K
V = 1640.03 (13) Å^3	Block, colourless
Z = 8	0.50 × 0.43 × 0.40 mm
F(000) = 704

Data collection

Bruker D8 Quest APEX3 diffractometer	7976 independent reflections
Radiation source: sealed tube	6730 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.030
Detector resolution: 10.4 pixels mm^-1	θmax = 36.5°, θmin = 2.5°
φ and ω scans	h = −19→19
Absorption correction: multi-scan (SADABS; Krause et al., 2015)	k = −23→22
Tmin = 0.703, Tmax = 0.747	l = −19→19
53075 measured reflections

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.042	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.126	H-atom parameters constrained
S = 1.05	w = 1/[σ^2(Fo^2) + (0.0699P)^2 + 0.3147P] where P = (Fo^2 + 2Fc^2)/3
7976 reflections	(Δ/σ)max = 0.001
222 parameters	Δρmax = 0.48 e Å^−3
0 restraints	Δρmin = −0.25 e Å^−3

Special details

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.

Refinement. Refined as a two-component twin.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
O01	0.10858 (7)	0.50152 (5)	0.16802 (7)	0.02241 (12)
O02	−0.14028 (7)	0.31769 (5)	0.35652 (7)	0.02335 (13)
O03	−0.07159 (7)	0.74381 (5)	0.32465 (7)	0.02290 (13)
O04	0.38859 (7)	0.67098 (5)	0.07120 (6)	0.02131 (12)
O05	0.56249 (7)	0.91448 (4)	0.40230 (6)	0.02143 (12)
O06	0.64980 (9)	0.48884 (5)	0.50429 (8)	0.03135 (16)
C07	0.01767 (7)	0.62606 (5)	0.24757 (8)	0.01641 (12)
H07	0.055272	0.676140	0.220862	0.020*
C08	−0.11303 (7)	0.57541 (5)	0.34891 (7)	0.01585 (12)
H08	−0.163797	0.590389	0.390752	0.019*
C09	0.03688 (7)	0.53026 (6)	0.22608 (8)	0.01607 (12)
C10	0.46028 (7)	0.69980 (6)	0.20008 (8)	0.01623 (12)
C11	−0.09212 (7)	0.47970 (5)	0.32589 (7)	0.01525 (12)
C12	−0.05762 (7)	0.64810 (5)	0.30898 (8)	0.01594 (12)
C13	0.60966 (8)	0.74637 (6)	0.47010 (8)	0.01768 (13)
H13	0.659966	0.761890	0.561868	0.021*
C14	−0.01837 (8)	0.45589 (6)	0.26492 (8)	0.01680 (12)
H14	−0.005616	0.390505	0.249828	0.020*
C15	0.55203 (7)	0.81845 (5)	0.37503 (7)	0.01604 (12)
C16	0.47689 (7)	0.79570 (6)	0.23988 (7)	0.01637 (12)
H16	0.437535	0.845382	0.175813	0.020*
C17	0.65223 (10)	0.57391 (7)	0.52876 (9)	0.02399 (16)
H17	0.696151	0.592882	0.619685	0.029*
C18	0.51868 (8)	0.62611 (6)	0.29356 (8)	0.01800 (13)
H18	0.508552	0.560727	0.266097	0.022*
C19	0.59175 (8)	0.65038 (6)	0.42732 (8)	0.01768 (13)
C20	−0.14979 (8)	0.40334 (6)	0.37109 (8)	0.01879 (13)
H20	−0.197577	0.422663	0.414534	0.023*
C21	−0.14813 (10)	0.76918 (6)	0.38642 (10)	0.02406 (16)
H21A	−0.235885	0.743391	0.333753	0.036*
H21B	−0.152196	0.839410	0.391306	0.036*
H21C	−0.108775	0.742127	0.476544	0.036*
C22	0.30925 (9)	0.74150 (7)	−0.02458 (8)	0.02306 (15)
H22A	0.251864	0.771607	0.004783	0.035*
H22B	0.257053	0.710378	−0.111097	0.035*
H22C	0.364524	0.790773	−0.032972	0.035*
C23	0.64453 (9)	0.94220 (6)	0.53742 (8)	0.02092 (14)
H23A	0.611474	0.914527	0.594092	0.031*
H23B	0.645839	1.012531	0.544393	0.031*
H23C	0.732586	0.918592	0.566549	0.031*
C24	0.17317 (10)	0.57404 (7)	0.13303 (11)	0.02795 (19)
H24A	0.108750	0.616172	0.064624	0.042*
H24B	0.226038	0.543502	0.098340	0.042*
H24C	0.228988	0.612158	0.212125	0.042*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O01	0.0291 (3)	0.0174 (3)	0.0313 (3)	−0.0012 (2)	0.0229 (3)	−0.0018 (2)
O02	0.0322 (3)	0.0155 (3)	0.0262 (3)	−0.0037 (2)	0.0170 (3)	−0.0008 (2)
O03	0.0310 (3)	0.0124 (2)	0.0347 (3)	0.0003 (2)	0.0233 (3)	−0.0003 (2)
O04	0.0257 (3)	0.0174 (3)	0.0159 (2)	0.0009 (2)	0.0060 (2)	−0.00314 (19)
O05	0.0276 (3)	0.0133 (2)	0.0164 (2)	0.0012 (2)	0.0050 (2)	−0.00162 (18)
O06	0.0421 (4)	0.0170 (3)	0.0329 (4)	0.0070 (3)	0.0164 (3)	0.0048 (3)
C07	0.0178 (3)	0.0140 (3)	0.0191 (3)	−0.0010 (2)	0.0103 (2)	0.0003 (2)
C08	0.0182 (3)	0.0144 (3)	0.0166 (3)	−0.0007 (2)	0.0097 (2)	0.0002 (2)
C09	0.0173 (3)	0.0151 (3)	0.0179 (3)	−0.0006 (2)	0.0101 (2)	−0.0004 (2)
C10	0.0170 (3)	0.0156 (3)	0.0160 (3)	0.0003 (2)	0.0078 (2)	−0.0015 (2)
C11	0.0176 (3)	0.0138 (3)	0.0148 (3)	−0.0011 (2)	0.0081 (2)	0.0007 (2)
C12	0.0181 (3)	0.0128 (3)	0.0179 (3)	−0.0005 (2)	0.0094 (2)	−0.0001 (2)
C13	0.0202 (3)	0.0162 (3)	0.0158 (3)	0.0023 (2)	0.0079 (2)	0.0009 (2)
C14	0.0201 (3)	0.0138 (3)	0.0185 (3)	−0.0007 (2)	0.0109 (2)	−0.0001 (2)
C15	0.0174 (3)	0.0137 (3)	0.0163 (3)	0.0012 (2)	0.0075 (2)	−0.0006 (2)
C16	0.0180 (3)	0.0144 (3)	0.0154 (3)	0.0011 (2)	0.0070 (2)	−0.0005 (2)
C17	0.0305 (4)	0.0185 (3)	0.0221 (3)	0.0059 (3)	0.0119 (3)	0.0045 (3)
C18	0.0210 (3)	0.0144 (3)	0.0193 (3)	0.0011 (2)	0.0102 (3)	−0.0002 (2)
C19	0.0206 (3)	0.0148 (3)	0.0183 (3)	0.0027 (2)	0.0098 (3)	0.0019 (2)
C20	0.0232 (3)	0.0161 (3)	0.0197 (3)	−0.0030 (2)	0.0125 (3)	0.0002 (2)
C21	0.0301 (4)	0.0173 (3)	0.0324 (4)	0.0023 (3)	0.0212 (4)	−0.0013 (3)
C22	0.0249 (4)	0.0231 (4)	0.0165 (3)	0.0040 (3)	0.0062 (3)	−0.0012 (3)
C23	0.0248 (3)	0.0175 (3)	0.0170 (3)	−0.0018 (3)	0.0072 (3)	−0.0029 (2)
C24	0.0334 (4)	0.0236 (4)	0.0400 (5)	−0.0051 (3)	0.0281 (4)	−0.0032 (4)

Geometric parameters (Å, º)

O01—C09	1.3594 (10)	C13—C19	1.4014 (11)
O01—C24	1.4297 (11)	C13—H13	0.9500
O02—C20	1.2144 (10)	C14—H14	0.9500
O03—C12	1.3624 (10)	C15—C16	1.4000 (10)
O03—C21	1.4292 (11)	C16—H16	0.9500
O04—C10	1.3609 (10)	C17—C19	1.4797 (12)
O04—C22	1.4321 (11)	C17—H17	0.9500
O05—C15	1.3623 (9)	C18—C19	1.3898 (11)
O05—C23	1.4275 (10)	C18—H18	0.9500
O06—C17	1.2120 (12)	C20—H20	0.9500
C07—C09	1.3918 (11)	C21—H21A	0.9800
C07—C12	1.4025 (11)	C21—H21B	0.9800
C07—H07	0.9500	C21—H21C	0.9800
C08—C12	1.3923 (11)	C22—H22A	0.9800
C08—C11	1.4003 (11)	C22—H22B	0.9800
C08—H08	0.9500	C22—H22C	0.9800
C09—C14	1.4014 (11)	C23—H23A	0.9800
C10—C16	1.3914 (11)	C23—H23B	0.9800
C10—C18	1.3996 (11)	C23—H23C	0.9800
C11—C14	1.3884 (11)	C24—H24A	0.9800
C11—C20	1.4795 (11)	C24—H24B	0.9800
C13—C15	1.3922 (11)	C24—H24C	0.9800
C09—O01—C24	117.83 (7)	O06—C17—H17	117.6
C12—O03—C21	116.74 (7)	C19—C17—H17	117.6
C10—O04—C22	117.72 (7)	C19—C18—C10	118.77 (7)
C15—O05—C23	116.88 (6)	C19—C18—H18	120.6
C09—C07—C12	119.48 (7)	C10—C18—H18	120.6
C09—C07—H07	120.3	C18—C19—C13	121.69 (7)
C12—C07—H07	120.3	C18—C19—C17	119.99 (7)
C12—C08—C11	118.39 (7)	C13—C19—C17	118.32 (7)
C12—C08—H08	120.8	O02—C20—C11	124.56 (8)
C11—C08—H08	120.8	O02—C20—H20	117.7
O01—C09—C07	123.95 (7)	C11—C20—H20	117.7
O01—C09—C14	115.37 (7)	O03—C21—H21A	109.5
C07—C09—C14	120.68 (7)	O03—C21—H21B	109.5
O04—C10—C16	123.58 (7)	H21A—C21—H21B	109.5
O04—C10—C18	115.74 (7)	O03—C21—H21C	109.5
C16—C10—C18	120.68 (7)	H21A—C21—H21C	109.5
C14—C11—C08	121.94 (7)	H21B—C21—H21C	109.5
C14—C11—C20	120.39 (7)	O04—C22—H22A	109.5
C08—C11—C20	117.66 (7)	O04—C22—H22B	109.5
O03—C12—C08	124.06 (7)	H22A—C22—H22B	109.5
O03—C12—C07	115.08 (7)	O04—C22—H22C	109.5
C08—C12—C07	120.86 (7)	H22A—C22—H22C	109.5
C15—C13—C19	118.47 (7)	H22B—C22—H22C	109.5
C15—C13—H13	120.8	O05—C23—H23A	109.5
C19—C13—H13	120.8	O05—C23—H23B	109.5
C11—C14—C09	118.66 (7)	H23A—C23—H23B	109.5
C11—C14—H14	120.7	O05—C23—H23C	109.5
C09—C14—H14	120.7	H23A—C23—H23C	109.5
O05—C15—C13	124.69 (7)	H23B—C23—H23C	109.5
O05—C15—C16	114.44 (7)	O01—C24—H24A	109.5
C13—C15—C16	120.86 (7)	O01—C24—H24B	109.5
C10—C16—C15	119.52 (7)	H24A—C24—H24B	109.5
C10—C16—H16	120.2	O01—C24—H24C	109.5
C15—C16—H16	120.2	H24A—C24—H24C	109.5
O06—C17—C19	124.76 (9)	H24B—C24—H24C	109.5
C24—O01—C09—C07	3.19 (13)	C23—O05—C15—C13	3.63 (12)
C24—O01—C09—C14	−176.62 (8)	C23—O05—C15—C16	−176.23 (7)
C12—C07—C09—O01	−179.69 (7)	C19—C13—C15—O05	−179.27 (8)
C12—C07—C09—C14	0.11 (12)	C19—C13—C15—C16	0.58 (12)
C22—O04—C10—C16	−10.72 (12)	O04—C10—C16—C15	179.72 (7)
C22—O04—C10—C18	169.48 (8)	C18—C10—C16—C15	−0.50 (12)
C12—C08—C11—C14	−0.02 (11)	O05—C15—C16—C10	179.48 (7)
C12—C08—C11—C20	178.95 (7)	C13—C15—C16—C10	−0.38 (12)
C21—O03—C12—C08	0.13 (12)	O04—C10—C18—C19	−179.06 (7)
C21—O03—C12—C07	179.77 (8)	C16—C10—C18—C19	1.13 (12)
C11—C08—C12—O03	179.42 (7)	C10—C18—C19—C13	−0.93 (12)
C11—C08—C12—C07	−0.20 (11)	C10—C18—C19—C17	178.64 (8)
C09—C07—C12—O03	−179.50 (7)	C15—C13—C19—C18	0.09 (12)
C09—C07—C12—C08	0.15 (12)	C15—C13—C19—C17	−179.49 (8)
C08—C11—C14—C09	0.28 (11)	O06—C17—C19—C18	4.47 (15)
C20—C11—C14—C09	−178.66 (7)	O06—C17—C19—C13	−175.94 (10)
O01—C09—C14—C11	179.50 (7)	C14—C11—C20—O02	−1.69 (13)
C07—C09—C14—C11	−0.32 (12)	C08—C11—C20—O02	179.33 (8)